<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>组件使用中的细节点</title>
    <script src='./vue.js'></script>
</head>
<body>

<div id="root">
    <counter ref="one" @change="handleChange"></counter>
    <counter ref="two" @change="handleChange"></counter>
    <div>{{total}}</div>
</div>
<script>

    Vue.component('counter', {
        template: '<div @click="handleClick">{{number}}</div>',
        data: function () {
            return {
                number: 0
            }
        },
        methods: {
            handleClick: function () {
                this.number++
                this.$emit('change')
            }
        }
    })

    var vm = new Vue({
        el: '#root',
        data: {
            total: 0
        },
        methods: {
            handleChange: function () {
                this.total = this.$refs.one.number + this.$refs.two.number
            }
        }
    })
</script>

</body>
</html>